215,785 views
2 votes
2 votes
6.36 g of glucose were dissolved in 500 ml of water. Find the molality of glucose in the solution.how is this calculated

User Sttwister
by
2.8k points

1 Answer

11 votes
11 votes

Answer:

Molality of glucose is 7×10⁻¹⁰ mol/Kg

Step-by-step explanation:


Molality = (Moles of solute)/(Kg of Solvent)

you need to do 2 things before use this formula:

1. Transform 6.36 g of glucose into moles

2. Transform 500 mL of water into grams

1. To transform 6.36 g of glucose into moles, we need to know the molar mass of glucose. The molecular formula of glucose is C₆H₁₂O₆

Molar Mass of:

O = 16

H = 1

C = 12

So, to calculate the molar mass of glucose:

(6x12)+(12x1)+(16x6) = 72 + 12 + 96 = 180 g/mol

Now:

6.36 g of glucose --- x moles

180 g of glucose --- 1 mol

x = 6.36/180

x = 0.035 moles

2. First, transform 500 mL into L = 0.5 liters.

To transform 500 mL of water into grams we need to know the density of the water. It is 997 Kg/m³.

liters to m³:

1 liter --- 0.001 m³

0.5 --- x

x = 5×10⁻⁴ m³

997 Kg --- 1 m³

5×10⁻⁴ --- x

x = 5×10⁻⁷ Kg

Now: 0.035 moles/5×10⁻⁷ Kg =

Molality of glucose is 7×10⁻¹⁰ mol/Kg

User Anil Konduru
by
3.5k points